【摘要】 3D VSP数据与地面地震数据相比接收噪音少、反射角信息比较丰富,更能直接反映波的运动学和动力学特征,因此,利用3D VSP AVO/AVA分析推测地层岩性和含油气性,为隐蔽性油气藏勘探提供有效技术手段。但是,用于AVA分析的VSP资料必须进行严格的振幅保持、地表一致性和角道集提取等精细预处理。本文采用全波场振幅补偿、两步法统计子波反褶积和直射线路径近似角度道集转换等适于3D VSP资料特点的精细预处理方法,最大程度地消除影响振幅的各种主要非地质因素,确保从角道集上得到的AVA响应是地下真实的AVA反映,取得了很好的处理效果。更多还原

【Abstract】 There are lesser receiving noise and richer reflecting angle information in 3D VSP data compared with surface seismic data.The kinematical and dynamic features of reflected wave can be presented directly.The stratigraphic lithology and hydrocarbon bearing ability can be predicted by 3D VSP AVO/AVA analysis.The effective technical means were provided for exploring subtle reservoir.The data used to AVA analysis should be preprocessed strictly by amplitude preserve,surface consistent,angle gathering extracting,and so on for meeting the needs of AVA analysis.Fine preprocessing methods,such as full wave field amplitude compensation,two-step statistics wavelet deconvolution and conversion of straight raypath aprx angle gathering were used in the paper to remove various chief non-geologic factors which affected the amplitude and to ensure the AVA respond from angle gathering which was the true AVA respond from underground.The good processing results were obtained.更多还原